We record an estimate of a loss when the loss is considered probable and estimable. Where a liability is probable and there is a range of estimated loss and no amount in the range is more likely than any other number in the range, we record the minimum estimated liability related to the claim in accordance with ASC 450, Contingencies. As additional information becomes available, we assess the potential liability related to our pending litigation and revises our estimates. Revisions in the our estimates of potential liability could materially impact our results of operations.

On July 27, 2018, AG Oncon, LLC, AG Ofcon, Ltd., Calamos Market Neutral Income Fund, Capital Ventures International, Citadel Equity Fund Ltd., Opti Opportunity Master Fund, Polygon Convertible Opportunity Master Fund, Wolverine Flagship Fund Trading Limited, as plaintiffs, filed a complaint in the Court of Chancery of the State of Delaware (AG Oncon, LLC v. Ligand Pharmaceuticals Inc.) alleging claims for violation of the Trust Indenture Act, breach of contract, damages and a declaratory judgment that the Supplemental Indenture, dated as of February 20, 2018, entered into by us and Wilmington Trust, National Association, as trustee, is invalid. On October 1, 2018, we filed a motion to dismiss the plaintiffs’ complaint. The hearing on our motion is currently scheduled for April 3, 2019. We believe the allegations are completely without merit, reject all claims raised by the plaintiffs and intend to vigorously defend this matter.

In November 2017, CyDex, our wholly owned subsidiary, received a paragraph IV certification from Teva alleging that certain of our patents related to Captisol were invalid, unenforceable and/or will not be infringed by Teva’s ANDA related to Spectrum Pharmaceuticals’ NDA for Evomela. On December 20, 2017, CyDex filed a complaint against Teva in the U.S. District Court for the District of Delaware, asserting that Teva’s ANDA would infringe our patents. On March 22, 2018, Teva filed an answer and counterclaims seeking declarations of non-infringement and invalidity as to each of the asserted patents and on April 12, 2018, CyDex filed an answer to Teva’s counterclaims. On July 24, 2018, the U.S. District Court entered a Scheduling Order, setting a hearing for April 1, 2019, and a trial may begin in January 2020.